Vitalism is the belief that internal bodily organs have agency and that they transmit or exchange a vital force or energy. Three experiments investigated the use of vitalistic explanations for biological phenomena by 5- and 10-year-old English-speaking children and adults, focusing on 2 components: the notion that bodily organs have intentions and the notion that some life force or energy is transmitted. The original Japanese finding of vitalistic thinking was replicated in Experiment 1 with English-speaking 5-year-olds. Experiment 2 indicated that the more active component of vitalism for these children is a belief in the transfer of energy during biological processes, and Experiment 3 suggested an additional, albeit lesser, role for organ intentionality. A belief in vital energy may serve a causal placeholder function within a naive theory of biology until a more precisely formulated mechanism is known.